Lamy Gustavo B, Cafarchio Eduardo M, do Vale Bárbara, Antonio Bruno B, Venancio Daniel P, de Souza Janaina S, Maciel Rui M, Giannocco Gisele, Silva Neto Artur F, Oyama Lila M, Aronsson Patrik, Sato Monica A
Department Morphology and Physiology, Centro Universitario FMABC, Santo Andre, Brazil.
Department Biological Sciences, Federal University of Sao Paulo, Diadema, Brazil.
Front Physiol. 2022 Jul 19;13:920636. doi: 10.3389/fphys.2022.920636. eCollection 2022.
Angiotensin-(1-7) is a peptide produced by different pathways, and regardless of the route, the angiotensin-converting enzyme 2 (ACE-2) is involved in one of the steps of its synthesis. Angiotensin-(1-7) binds to Mas receptors localized in different cells throughout the body. Whether angiotensin-(1-7) exerts any action in the urinary bladder (UB) is still unknown. We investigated the effects of intravenous and topical () administration of angiotensin-(1-7) on intravesical pressure (IP) and cardiovascular variables. In addition, the Mas receptors and ACE-2 gene and protein expression were analyzed in the UB. Adult female Wistar rats were anesthetized with 2% isoflurane in 100% O and submitted to the catheterization of the femoral artery and vein for mean arterial pressure (MAP) and heart rate (HR) recordings, and infusion of drugs, respectively. The renal blood flow was acquired using a Doppler flow probe placed around the left renal artery and the renal conductance (RC) was calculated as a ratio of Doppler shift (kHz) and MAP. The cannulation of the UB was performed for IP recording. We observed that angiotensin-(1-7) either administered intravenously [115.8 ± 28.6% angiotensin-(1-7) vs. -2.9 ± 1.3% saline] or topically [147.4 ± 18.9% angiotensin-(1-7) vs. 3.2 ± 2.8% saline] onto the UB evoked a significant ( < 0.05) increase in IP compared to saline and yielded no changes in MAP, HR, and RC. The marked response of angiotensin-(1-7) on the UB was also investigated using quantitative real-time polymerase chain reaction and western blotting assay, which demonstrated the mRNA and protein expression of Mas receptors in the bladder, respectively. ACE-2 mRNA and protein expression was also observed in the bladder. Therefore, the findings demonstrate that angiotensin-(1-7) acts in the UB to increase the IP and suggest that this peptide can be also locally synthesized in the UB.
血管紧张素 -（1 - 7）是通过不同途径产生的一种肽，无论其产生途径如何，血管紧张素转换酶2（ACE - 2）都参与其合成的其中一个步骤。血管紧张素 -（1 - 7）与遍布全身不同细胞中的Mas受体结合。血管紧张素 -（1 - 7）是否在膀胱（UB）中发挥任何作用仍然未知。我们研究了静脉内和局部（）给予血管紧张素 -（1 - 7）对膀胱内压（IP）和心血管变量的影响。此外，还分析了膀胱中Mas受体以及ACE - 2基因和蛋白的表达。成年雌性Wistar大鼠用含2%异氟烷的100%氧气麻醉，分别经股动脉和静脉插管以记录平均动脉压（MAP）和心率（HR），并用于输注药物。使用置于左肾动脉周围的多普勒血流探头获取肾血流量，并将肾电导（RC）计算为多普勒频移（kHz）与MAP的比值。进行膀胱插管以记录IP。我们观察到，静脉内给予血管紧张素 -（1 - 7）[血管紧张素 -（1 - 7）组为115.8±28.6%，生理盐水组为 - 2.9±1.3%]或局部给予[血管紧张素 -（1 - 7）组为147.4±18.9%，生理盐水组为3.2±2.8%]膀胱后，与生理盐水相比，IP显著升高（<0.05），而MAP、HR和RC无变化。还使用定量实时聚合酶链反应和蛋白质印迹分析研究了血管紧张素 -（1 - 7）对膀胱的明显反应，结果分别证明了膀胱中Mas受体的mRNA和蛋白表达。在膀胱中也观察到了ACE - 2的mRNA和蛋白表达。因此，这些发现表明血管紧张素 -（1 - 7）在膀胱中发挥作用以增加IP，并提示该肽也可能在膀胱中局部合成。
